The present invention relates to an electrode seal assembly for a metallurgical furnace. More particularly this invention concerns a seal for use where a carbon electrode passes through the wall of a gas-tight furnace used for electric-arc refining and the like.
It is standard practice to operate an electric-arc furnace or the like in a special gas. Such a furnace has a single gas vent that is controlled by an automatic valve that maintains a predetermined pressure in the furnace.
Obviously leakage cannot be permitted at the holes in the furnace wall where the electrodes project into the interior of the furnace, these electrodes normally being relatively large cylindrical graphite rods. Since the electrodes are slowly consumed at their inner ends by the process, it is essential also that they be axially displaceable inward through the furnace wall.
The seal assembly must be as small as possible. Hence it cannot carry extensive shielding and will be exposed to the high heat in the furnace. As a result the adjustable components of the seal assembly degrade quickly. When robust parts are used the seal becomes too large and normally does not seal tightly.